Article preface

This article is not meant to be an exhaustive setup guide and assumes that the reader has setup an Arch system before. Arch newbies are encouraged to read the Beginners' guide if unsure how to perform standard tasks such as creating users, managing the system, etc.

Installing Arch Linux ARM

Resize filesystem

The image size is 2GB. In order to expand the root filesystem to use the whole SD card (assuming it is bigger than 2GB), please follow some of the existing guides.

Network

Enable IPv6

IPv6 is disabled by default. To enable it, remove ipv6.disable=1 from the beginning of /boot/cmdline.txt.

Configure wlan without network or display

By default a fresh install will connect to a connected LAN with dhcpcd. If you want to access your Raspberry Pi via wlan from the start, create the necessary files on the sdcard. You need a netctl profile and enable the systemd unit netctl-auto.

Mount the sdcard-partition5

# mount /dev/mmcblk0p5 /mnt

Create a netctl profile, if you use netctl on your main machine, you can just copy one

# cp /etc/netctl/profilename /mnt/etc/netctl/

or you can adapt one from the /examples directory /etc/netctl/examples. Make sure the profile uses interface wlan0 not wlpsXsX.

To automatically connect to an available network enable the systemd unit netctl-auto.

Caveats for HDMI audio

Video

HDMI / analog TV-Out

Use the -s parameter to check the status of your display, the -o parameter to turn your display off and -p parameter to power on HDMI with preferred settings.

Adjustments are likely required to correct proper overscan/underscan and are easily achieved in boot/config.txt in which many tweaks are set. To fix, simply uncomment the corresponding lines and setup per the commented instructions:

# uncomment the following to adjust overscan. Use positive numbers if console
# goes off screen, and negative if there is too much border
#overscan_left=16
overscan_right=8
overscan_top=-16
overscan_bottom=-16

Users wishing to use the analog video out should consult this config file which contains options for non-NTSC outputs.

A reboot is needed for new settings to take effect.

X.org driver

The X.org driver for Raspberry Pi can be installed with the xf86-video-fbdev package:

# pacman -S xf86-video-fbdev

Onboard hardware sensors

Temperature

Temperatures sensors can be queried with utils in the raspberrypi-firmware-tools package. The RPi offers a sensor on the BCM2835 SoC (CPU/GPU):

Overclocking/underclocking

The optional *_min lines define the minimum frequency to be used for the given component. When the system is not under load, the frequencies will drop down to the minimum value. Consult the Overclocking article on elinux for additional options and examples.

A reboot is needed for new settings to take effect.

The overclocked setting for CPU clock applies only when the governor throttles up the CPU, i.e. under load. To query the current frequency of the CPU:

Hardware random number generator

ArchLinux ARM for the Raspberry Pi is distributed with the rng-tools package installed and the bcm2708-rng module set to load at boot (see this), but we must also tell the Hardware RNG Entropy Gatherer Daemon (rngd) where to find the hardware random number generator.

This can be done by editing /etc/conf.d/rngd:

RNGD_OPTS="-o /dev/random -r /dev/hwrng"

and restarting the rngd daemon:

systemctl restart rngd

Once completed, this change ensures that data from the hardware random number generator is fed into the kernel's entropy pool at /dev/random.